Hi @satello
It could be a number of reasons, but a common one is another plug in interfering, however I notice you mention you don’t have any other plugins, which does seem a little odd!
Before you load the Barclays page, if you press F12, this will bring up an error console. If there are any errors with it loading, they should be shown here. If you can share these with us, we can hopefully point you in the right direction.
You need to set this up with Barclays. We have a guide on how to do this here.
Hope that helps!